In late December, someone contracted measles. Then, he or she went to Disneyland.
Now, thanks to the transfer of the measles virus at either Disneyland or its neighbor, Disney California Adventure Park in Anaheim, California, an outbreak is spreading across the state.
By January 26, 73 cases of measles had been confirmed among California residents, according to the California Department of Public Health (CDPH). Among those cases, 50 have been linked to an initial exposure at a Disney park. By January 21, five cases had been reported among Disney employees, CDPH officials stated in a press release, and in January other people had visited the parks while infectious.
Alameda County accounts for five of the current measles cases in California, with four linked to Disneyland, said Sherri Willis, the spokesperson from the Alameda County Public Health Department (ACPHD). (The state’s CDPH website, last updated January 26, linked only three of the five cases to Disney exposure.) Alameda County is investigating “many other suspect cases,” according to the public health department’s website. Only four measles cases were confirmed in the county in all of 2014.
Contra Costa County currently doesn’t have any confirmed measles cases. The last time there were cases of the disease in the county was in 2014, after a UC Berkeley student who lived in the area became infected. Back then, the disease spread to three other people. “Those four cases in our county were the first one of measles cases in five years,” said Paul Leung, immunization coordinator at Contra Costa Health Services (CCHS). “Neither the student nor the sick relatives were vaccinated against measles,” stated CCHS in a press release in 2014.
Now measles have spread beyond Disneyland, the state and even the country.
By January 26, 8 states including California, Utah, Oregon, Arizona, Nebraska, Colorado and Washington had measles cases, and Mexico reported one case. Fourteen of the cases outside of California have been epidemiologically linked to Disney, according to CDPH’s website.
It is still unknown who started the outbreak, the largest since measles elimination was documented in the United States in 2000, the Centers for Disease Control and Prevention (CDC) states on its website. Nonetheless, measles is still widespread in several parts of the world, such as Europe, Africa and Asia.
Dr. Gil Chavez, deputy director of the CDPH’s Center for Infectious Diseases, said in a press release that any patient with a measles-like illness, who has recently visited places international travelers gather, like airports, should be considered to have “a plausible exposure to measles.”
“It is absolutely safe to visit these places, including the Disneyland Resort, if you are vaccinated,” Chavez added.
While Disney has not released any statements confirming the number of infected employees, spokespeople have said the company is monitoring the health of its workers, whom it refers to as “cast members.” In a message posted on the Disneyland public affairs web page, Dr. Pamela Hymel, Chief Medical Officer for Walt Disney Parks and Resorts, wrote, “A small number of cast members have tested positive and as they are medically cleared, they have been returning to work. In addition, cast members who may have come in close contact with those who tested positive are being tested for immunity to the virus.”
Employees who cannot verify their immunization history will be offered a blood test, a Disney spokesperson wrote by email, and employees who may have come into close contact with someone who has measles will be required to take paid leave from work until Disneyland has confirmed their immunity status. The spokesperson also wrote that the company is offering vaccinations, and is requiring anyone who chooses not to be vaccinated to stay home through the incubation period, during which an exposed person could become infected.
Officials at Six Flags Discovery Kingdom in Vallejo, the Bay Area’s closest major theme park, did not return interview requests.
Measles is caused by a virus and is one of the most contagious diseases, as the virus travels easily through the air. Every time an infected person coughs, sneezes, or shares edibles measles can be spread to other people.
The disease typically begins with fever, cough, pink eyes and runny nose. It is only a few days later that a red rash appears—first on the face and then spreading to the rest of the body. But people can be infectious for a few days before developing these symptoms, and may expose others to the disease without being aware of it.
For that reason, health authorities are encouraging people to contact their health care providers if they have symptoms and think they may have been exposed. In that case—and unless it is an emergency—“it is best to contact your health care provider by phone to prevent spread to the doctor’s offices,” said Ron Chapman, director of the CDPH, during a conference call held on January 21. “The best way to prevent measles and its spread is to get vaccinated,” he added.
Although it is still not known exactly how this outbreak originated, health experts agree that vaccination is important to prevent this kind of disease. Most of the reported cases of measles in California between December and January 21 were among people who were not immunized, said Chavez during the conference call. Among the five Alameda County cases, of those for whom there’s vaccination history available, half were unvaccinated, said Willis.
Measles vaccines have been available in the United States since 1963. For the last 25 years, health experts have recommended two doses of the measles vaccine. Children get their first dose of the MMR (measles, mumps, rubella) vaccine at one year old or later, while the second dose is usually administered before the child begins kindergarten.
As part of Contra Costa County’s immunization program, the county works with schools, childcare, kindergarten and 7th grade students to ensure they meet state immunization requirements. It also works with healthcare providers and clinicians on how to report the disease. “We work to vaccinate all members of our community throughout the age spectrum; from babies to teenagers to adults, to the elderly,” said Leung. “All of them can benefit from being protected by vaccines.”
Alameda County also works with parents, physicians, clinics, and schools, among others, through its Immunization Assistance Project. Its goal is to help adults and children get vaccinated against diseases that can be prevented.
Other programs, like the federally-funded Vaccines For Children, provide children with free vaccines against 16 diseases, including measles.
Some parent’s lack of access to health care prevents them from vaccinating their children. In other cases, parents file a Personal Belief Exemptions (PBE), making the decision to not vaccinate their children due to philosophical or religious reasons. “In the past few years, we are seeing a growing number of parents who are choosing to exempt their child from one or more school-required doctor-recommended vaccinations,” said Leung.
But that might be starting to change. A modification in the process for getting a PBE was introduced last year, which makes sure that parents who are considering exempting their child from vaccination meet with their health care provider. That way they can discuss the risks and benefits of vaccination, as well as the risks of the disease, and “make an informed decision,” said Leung.
Contra Costa County’s overall PBE percentage for all childcare facilities (public and private) decreased from 2.91 percent in 2013 to 2.42 percent in 2014, according to numbers provided by Leung. That is almost a 17 percent reduction in the number of exemptions. Leung said that “a roughly 2 percent PBE county wide level may seem small,” but actually exemption levels can be much higher at certain schools. The county has mapped its childcare and schools by exemption levels via an online tool for parents and other community members.
The number of unvaccinated people is still a matter of concern among health experts, who are now emphasizing their message: Get vaccinated or know whether you are already immune. People born before 1957 are consider to be immune to measles, because back then the virus was so widespread that “virtually everyone” had the disease, said Arthur Reingold, professor and head of Epidemiology at the UC Berkeley School of Public Health.
So does it make sense to vaccinate an adult? According to Reingold, it depends on what country you are in, among other factors. In the U.S., measles is not often a fatal disease. “But it does kill some people in the developing country setting,” he said.
In the U.S., it also depends on the age of the adult. Because of programs that routinely immunized infants several decades ago, ”There are very few adults walking around the U.S. who require vaccination,” Reingold said. But children may be at more risk. The disease can sometimes progress to lung infection (pneumonia) and brain infection (encephalitis), leading to severe or fatal cases. Being very young when getting the disease, or having HIV or immune depression due to another health condition, are the primarily factors that can lead to more serious cases of measles.
“For those who doubt the wisdom of vaccinating their child, this outbreak is “a good example of why that’s not an intelligent strategy,” said Reingold, adding: “We have a very safe and effective vaccine, so we should use it.”
“The more unimmunized people we have, the greatest the risk that we’ll have multiple generations of cases and bigger outbreaks,” he continued.
California health authorities are delivering the same message. “People who are unvaccinated should know that there is presently a risk for acquiring measles in California,” states the press release from CDPH.
Reingold said he expects another wave or two of infections before the outbreak stops, “but I do expect this to get it back under control and end the outbreak,” he said.
ACPHD’s Willis added that the outbreak is especially dangerous to unvaccinated people. “Measles is now circulating in that community and not just isolated to Disneyland,” she said. “This makes the ‘get vaccinated’ message even more relevant.”